Miner&#39;s electric lamp bulb



July 6, 1937. A. e. GULLIFORD MINERS ELECTRIC LAMP BULB Filed Feb. 25, 1957 INVENTUR A fie/E GULLIFoRD, r

' Au s Patented July 6, 1937 PATENT OFFICE MINERS ELECTRIC LAMP BULB Albert George Gulliiord, Conisborough, near Rotherham, England Application February 23, 1937, Serial No. 127,152

In Great Britain March 3,1936

1 Claim.

This invention relates to improvements in miners electric lamp bulbs and has for its object to provide a fuse wire and fuse wire holder fitted to the bulb cap and connected to one of the bulb 5 filament wires such that in the event of the bulb becoming broken and the filament wires being forced together the fuse wire fuses inside the fuse holder and prevents any heating or sparking of the exposed filaments when current from a miners lamp battery passes through the lamp bulb.

Accordingly the present invention may be said to comprise a miners lamp bulb having an insulated base inside the bulb cap to receive a metal tube, screw, or socket or light which has in turn one of the filament leading-in wires of the bulb attached, and connected thereto one end cap of a cartridge fuse with fuse wire therein, the other end cap of the fuse forming one of the contacts of the lamp bulb.

The invention will now be described more particularly, reference being taken to the accompanying drawing in which Figure 1 shows a sectional arrangement through the bulb with filaments and fuse wire intact; Fig. 2 shows a sectional arrangement through the bulb as it would appear when the bulb globe is broken and filament wires pressed together and fused; Fig. 3 shows an elevation through a bulb similar to Fig. 1 but with a bulb cap of screw type.

Figs. 1, 2, 3 each show an embodiment wherein the insulated base A is arranged in the bulb cap B. The base A is recessed at al drilled out at a2 and provided with a metal tube. screw, or socket C. The screw or socket C is drilled through at at to allow the filament leading-in wire ft to fit in.

The globe E fitted with leading-in wires fl and f2 is then placed in cap B with a section of leading-in wire fl fitting in tube, screw, or socket C and soldered or otherwise secured at 02. A section of filament leading-in wire f2 is then soldered on cap B at bl. Globe E and base A with their fittings are then fixed in cap B by means of plaster, cement or like compound G. The cartridge fuse I-I comprises an insulated tube J fitted 10 at each end with a metal cap K. A fuse wire L is provided in the insulated tube J and connected to each of the metal caps K, in the usual way. One end of the fuse holder H is then fitted in the underside of cap B coming flush up to the tube, screw, or socket C on base A thus forming a connection through fuse wire L to filament leading-in wire ft. The other end of fuse holder I-I projects below cap B for the purpose of forming" a connection with aminers lamp battery. The 20 fuse holder H with its fittings is then fixed in cap B and base A by means of plaster, cement or like compound G.

I claim:-- 7 A A lamp bulb for miners electric lamps provided 25 with a fuse Within the cap, characterized by a base plate of insulating material embedded in suitable cement within a metal lamp cap, a socket member fitted to said insulating plate and connected to one end of the filament, a fuse carried 30 in said socket member and embedded in cement, the other end of such fuse protruding at the cap surface to form due contact of the lamp bulb.

ALBERT GEORGE GULLIFORD. 35 

